超声电火花复合加工速度工艺试验研究

Experimental Research on Small Holes by Electrical Discharge Machining Combined with Ultrasonic Vibration

电火花加工的最大缺点是加工速度低,为了解决这个问题,人们进行了各种试验研究。其中超声电火花复合在加工小孔中可一定程度地提高加工速度,但就其作用机理和适用范围仍存在许多争论。本次试验在D703F高速电火花小孔加工机床上附加陶瓷换能器和变幅杆,通过夹紧装置将变幅杆与工具电极相连,实现电极超声振动的电火花小孔加工。在不同的电参数(电流强度和脉冲宽度)和电极参数(电极直径)下,进行了2种加工方法下的加工速度对比试验。找到了在加工小孔时,是否采用超声电火花复合加工工艺的分界点,对其增加加工速度的现象提出了新的解释。

EDM has one serious disadvantage that the material removal rate (MRR) is low, so much theoretical and experimental works have been done. The ultrasonic vibration electrical discharge machining (UEDM) can improve the MRR in small hole machining, but the mechanism and process of UEDM is still arguable. The experiments are done in D703F (high velocity electro discharge small hole machine). A transducer and horn are attached between the spindle and the electrode. The horn and the tool electrode are connected together by a chucking appliance. With the electrode vibrating, the UEDM is achieved. The comparison experiments of the MRR are carried out with different electricity parameters (such as electric current, pulse duration, etc.) and different electrodes. The experimental results show that the reference point for UEDM is found and the new theory is proposed to explain the MRR increase.